Technical Field
The present invention relates to a course estimator for estimating a state of a course of a vehicle and a non transitory computer-readable storage medium for the same.
Related Art
Conventionally, there has been known a device mounted on a vehicle for estimating a road shape (referred to as a course shape) of the forward traveling path to which the own vehicle is going to travel (see PTL1 (JP 2009-9209 A)).
The device disclosed in PTL1 detects the turning direction (and the turning radius) of the own vehicle on the basis of detection results (i.e. yaw rate) of a yaw rate sensor or detection results (i.e. steering angle) of a steering angle sensor. Further, the device estimates the course shape as the detected turning radius and turning direction of the own vehicle under the assumption that the detected turning radius and turning direction are kept on the forward travelling path of the own vehicle.
However, on a road where the curvature changes, the device disclosed in PTL1 cannot detect the changing point of the curvature, because the device estimates the course shape under the assumption that the detected turning radius and turning direction at specified time are kept on the forward traveling path of the own vehicle. In the device disclosed in PTL1, this causes a deviation of the estimated course shape from the actual course shape of the forward traveling path.
That is, the method of estimating the course shape by the device disclosed in PTL1 has poor accuracy for estimating the course shape.
This disclosure has its object of improving accuracy for estimating a course shape in a course estimator.